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F1 Rocket and RV4 or RV8 relations? They family?

Kartracer44

I'm New Here
Can someone help me clear some things up. I'm still not too sure on what the f1 rocket is. Is it suppose to be a completely new fuselage but uses RV4 wings? Is it a modified RV4 Fuselage? Are there parts in it from an RV8? Is it using an rv4 wing that is slightly modified? its confusing on how it relates to the Vans RV aircraft.
 
From what I understand the F1 Rocket is a different aircraft to the Harmon Rocket 2.

The Harmon Rocket 2 is a modified RV-4 with a huge engine on the front. Basically you order an RV-4 kit, then the kit from Harmon, and you have yourself a Rocket.
https://www.harmonrocket.com

The F1 Rocket in a separate aircraft marketed by Team Rocket based in Texas.
https://www.teamrocketaircraft.com/

That's my understanding of it anyway.
 
F1 vs Harmon vs RV4

The RV4 is 100% Vans design/parts, the Harmon starts with an RV-4 kit , and supplemented with a Harmon designed mod kit that changes wing rib spacing, fuselage components from the cockpit forward and landing gear, cowling, ect required for the big engine. F1 Rocket has zero RV/Vans parts and was independently developed, but obviously uses some similar design theory. Most RV-4s and Harmon Rockets will have tip over canopy and F1 Rockets will have a slider canopy with the "speed slope" forward windshield. There are a couple Harmon variants, and a few F1's have a unique tapered wing. Rockets are marvelous aircraft for climb and brute power, but the RV-4 has the lightest control feel and much less $$. I have flown both the F1 and RV-4, and would love to have one of each, but budget says RV-4 only, which is what I built and fly. I may have left out some details, but that's the basic differences.
 
It's both simpler and more complex than that. A whole lot could be written here. In very brief summary from what I'm trying to remember:

RV-4 - A well known Vans product. Designed around a relatively lower HP engine.

HR2 - "Based" on the RV-4 in that it utilizes a lot of the same components. The fuse was widened by 4 inches. The wings were re-stationed (which subsequently made them shorter) to stiffen them against flutter. designed around an IO540, 250 HP powerplant. Vne= 275 mph. https://www.harmonrocket.com/

F1 Rocket - Long history there but gonna skip forward to the present. The link in the previous post is not current.

F1 Aircraft - Company now based in IN. Lots of combos of configurations. RV4 wings. RV8 wings, the aforementioned "Rocket" wings. Four cylinder Lycs to six cyclinder Lycs and Conties. Have heard of at least one that claims to have >400HP up front. The original Team Rocket business owner/pilot/builder races his at Reno. Slider canopies with bubble or sloped fronts. Floppers. RV4 tail feathers through their newest ones purpose designed for higher speeds. Future tapered wings are an on going project. Could go on.
So much would depend on your needs and desires. Not every/any combo of the aforementioned would be wise or optimal. Someone more knowledgeable will hopefully chime in.
 
I have built and flown all the variations of RV4, Harmon, and F1. I have also built a few more F1s with standard wings, a RV7, and a RV10. I currently own a F1 with a tapered wing which I build in 2006. I am still flying that plane and it will very likely be my last airplane. It is not for everyone, only because everyone has not flown one!

Many thanks to Mark Fredrick for designing my perfect airplane.
 
I love my EVO and its my favorite airplane. Probably the last airplane i will own. gets it on and does great at high altitudes. Great cross country performer
 
Thank you Everyone!

Thank you everyone for replying, this really cleared alot of things up. Then i read FreeMasms reply and i got confused again when he stated that the F1 comes configured with either RV4 or RV8 wings, 4 or 6 cylinder engines, and other things. Seems like there's no set design that is common to the plane. Like a frankenstein of various planes? The F1 rocket website has quite a few broken links so not sure if they just forgot about the website or if they're still in business. Seems like Tom and Rob really like the Rockets. How does the handling of the F1 or Raider compare to the RV4? Is it a better handling aircraft? Or is the Harmon Rocket 2 a middle ground between the two?
 
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Lessee here…

I started TeamRocket in 2000 to use the help from the CZ boys building the wings and fuselages and parts to finish the build. I sold 175 kits - some still waiting for assembly! 2008 came along and smashed everything. The remaining parts were put in storage (for what reason - I must have been out of my head?)

Vince called and we decided to transfer all usable parts to him and maybe the system would more or less restart. We were right about that - luckily.

Vince copied Larry Vetterman’s 4 cyl engine and started that path, along with the Sport Wing F1. The Evo wings were/are not available - but Vince met up with an engineer in CO who wanted to build a different tapered wing. That project has yet to produce a viable product - so the ‘Sport wing” was the only version of a wing that would allow customers to build a parts-only version of the F1 Sport wing.

I saw a centersection that fit the F1 but used the RV-8 wings - I can’t say if that project is still viable. I am also not sure about the -8 wing being a Good Thing to put into an F1 after seeing what some F1 Owners do to their aircraft!

I still help with customer questions if Vince gets backed up - as he is now with a new setup in N Indiana.

There is more (composite Evo wings made in the Ukraine; metal Evo wings made here in the USA) but those projects did not work out - yet. If enough fellas step up, I could get the Evo wing into production, but I do not want to start up and run the project at 67 years old. I would help with the startup if someone else would fund it…maybe.

That’s my story an’ I’m stickin’ to it.
 
After moving to northern Nevada from Texas, I have determined that when it comes to these aircraft, if you say “Rocket” west of Salt Lake, everyone assumes you’re talking about a Harmon, and if you say it east of Salt Lake, they assume you mean an F1…..

:) ;)
 
There is another thread started by Steve Smith where it looks like they are getting close to test flying a tapered, carbon wing. That would be an awesome match, if they were interested in producing them for sale?
 
I want to point out that Mark supported me a great deal when I built a Harmon Rocket.

He sold me a sliding canopy, SS windshield, wheel pants, spinner, and a propeller (at least) and provided me a lot of free advice.

Specifically, he gave me the formula for reinforcing the horizontal stabilizer, which I implemented.

Thanks, Mark!
 
Adding to the Drift

To the OP: Between tail feathers, wings, canopies and FWF, the “Rocket” may be the most mixed and matched EAB aircraft flying.

I want to point out that Mark supported me a great deal when I built a Harmon Rocket.

He sold me a sliding canopy, SS windshield, wheel pants, spinner, and a propeller (at least) and provided me a lot of free advice.

Specifically, he gave me the formula for reinforcing the horizontal stabilizer, which I implemented.

Thanks, Mark!

Ditto: Mark and Vince are great!

vlittle, or Mark, care to share the specifics of the Harmon horizontal stab reinforcement? I’ve read every Rocket thread here on the forum and don’t recall it being covered.
 
Vince here. Let me say a few things here:

1) No, we're not out of business, nor do we plan to be.

2) Yes, we've had continual trouble with our website. Blake is supposed to be migrating it to a new hosting service soon. In the meantime the website will probably continue to be troublesome. Very sorry, but please remember we're airplane nerds not tech geeks. The website is the lowest priority to us. Absolutely bottom of the list.

3) As Mark mentioned, I tried to pick up where he left off starting in 2016. We have everything made in the U.S.

4) There are no quick build kits. And until we finish the new wing, there are no tapered wings available. The sport wing is a great wing and it is still available partly through us and partly through another well-known company. We are working through those parts, and have spars, ribs, and skins. We do not make the control surfaces yet.

5) As others have mentioned, there are more options as to how to build this airplane than there used to be. However, the RV8 wings are no longer among the supported options.

6) In spite of any rumors to the contrary, the Rockets were never based on the RV-8.

7) IMPORTANT: We're building a new shop ( and home) near Cutler, INDIANA. We're in the middle of the construction and the move. Because of this, we're not taking any new kit orders at this time. We are, however, doing our best to get necessary parts to our existing customers. This is solely due to the construction and move, and not anything to do with price of gasoline or any current political situation. Please refrain from speculating as it will certainly be incorrect.

8) Come see us at Oshkosh for a face to face discussion.

Cheers!
Vince
 
I want to point out that Mark supported me a great deal when I built a Harmon Rocket.

Yeah. If I've neglected to say it, Mark is a class act.

True story. Many moons ago I thought I wanted a Rocket. Called Mark. No kits available, but if I gave him a large deposit he would see about getting one from Europe for me. I didn't know Mark from Bob's housecat, so I said no thanks.

Six months or more later, Mark called one day to say a customer would not be building his kit, and asked if I would like to buy it. I had already started a new project and had to pass, but I was very impressed. Mark was spending time helping two customers at no gain to himself.
 
Vince I hope your new shop build is going better than mine! I’m a month into clearing/construction and still don’t have footings poured. Hope this isn’t an omen to my future Rocket project….
 
Mark and Vince

TOTALLY agree that both these gentlemen are very giving of their time and expertise.Fine examples of the homebuilding community. Truly appreciated
 
I own harmon rocket II serial #1. It was built by john harmon at the factory for his dentist friend. It was the first airplane built using all the production kit parts. It is based on the rv4 kit with the usual known harmon mods to turn it into a rocket. The one thing I found strange when talking to john on the phone was that this airplane was built with a modified rv6 wing instead of the rv4 wing. It is lighter on the controls than my previous rv4 in both roll and yaw. The pitch is heavier, but I do have the f1 modified bell crank that makes it very nice to fly. It flies great, cruises fast and climbs like you would not believe with a 540, 10-1 pistons and ram air. I can go 195ktas on 15 gph above 8000ft DA or I can go 155 ktas at 1000ft and 18”/2200rpm on 9gph. It makes me giggle like a school girl everytime I fly it. I also love the extra room in the cockpit and never have to worry about performance or being overloaded.
 
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F1 Spinner??

What is the part number for the large spinner that fits the F1 cowl? and who sells it??

Thanks,

Phil
 
I purchased Jim Winings F1 Rocket. Tom and Vince provided me a lot of their time and advice for a total cost of zero! You won’t find more helpful people anywhere. With Jim’s mod to the bellcrank and RocketBobs stabilizer the aircraft is delightful to fly. Mine is probably the only F1 with a flopper canopy. I planned on switching to a slider however after flying with the flopper for a year realized I loved it and canceled the plans for the slider. I suspect Jim would approve and understand why he built it that way. Plus I am 65, much easier in and out!
 
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By titanhank

this airplane was built with a modified rv6 wing instead of the rv4 wing

Now I’m puzzled… what’s the difference between a -4 and a -6 wing, but for the wing walk on both sides for the -6?
 
The most obvious difference between RV-4 & RV-6 wings would be the length of the spar inside the fuselage. The 4 is narrower so has a shorter spar.

The fuel tanks in a 4 are smaller than the 6 tanks & both are smaller than the 7 tanks.

There are dimensional differences in wing area as well. The Harmon conversions to the RV-4 wings also called for shortening the 4 spars for less wing span too.
 
Thanks Ralph, that all checks out.
Yep, tank capacity was increased on the -6. But what about the total wing spar length?
Span being the same, the effective lifting wing area is smaller on the -6, but still wonder about the spar differences… if any?
 
4 & 6 spars look very similar other than lengths. Same number and thickness of bars used on both models. Diagrams in downloadable plans look the same.

Earlier paper plans (geared to also support those wanting to scratch build) would have all dimensions of components used where the downloadable plan set don't seem to.
 
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Vince has a gent that makes a CF spinner.

Sure but for what spinner/backplate? Did not see where he specified. Would definitely stick with the related OEM for such unless no other option.

Should be Propeller/backplate.
 
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Sure but for what spinner/backplate? Did not see where he specified. Would definitely stick with the related OEM for such unless no other option.

The OEM spinner has a huge blade cutouts and is expensive. The gent who makes the spinner is a friend of Vince and I and as I recall has the molds for the bulkheads as well.
 
Hartzell two blade? CY or BA? Three blade composite?Hartzell, WW, MT?

If the inquirer stated, didn’t see it on the phone screen.
 
Specific Differences

Now I’m puzzled… what’s the difference between a -4 and a -6 wing, but for the wing walk on both sides for the -6?

I recently did a side by side plans comparison of the -4, -6, and HRII Rocket wings due to a construction question regarding my Rocket project’s aileron and flap rigging.
I was surprised to learn that the -4 wing is 8.5 inches LONGER than the -6’s.
The -4 wing as modified by Harmon’s plans is virtually identical to the -6 wing.
Rocket wing exceptions:
-5/8 in. shorter in length
-flap is 3/8 in shorter to account for different fuselage side profile.
-extra bay in fuel tank netting 21 gal. per side.
-shortened spar carry-through to account for different fuselage widths.

Question: Given the -6’s excellent performance with a “Harmon Rocket” wing, I’m curious, why is the F4 Raider built with a standard -4 wing vice the “Sport” wing of the F1?
 
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Question: Given the -6’s excellent performance with a “Harmon Rocket” wing, I’m curious, why is the F4 Raider built with a standard -4 wing vice the “Sport” wing of the F1?[/QUOTE]

This is a great question. I don't fully understand it except that, in developing the F4 Raider, Mark Frederick prefers builders use standard length RV4 wings. He explained that the lower wing loading of the standard wing permits using less horsepower and yields better performance at higher altitudes.

My question is what density altitude is optimal for best cruise for each plane? Would a 6 cylinder 260+hp Rocket with sport wings and a 200hp 4 cylinder Raider with standard -4 wings cruise efficiently at the same altitudes? Only slightly slower than the 6 cylinder?
 
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So many questions...whew.

Fortunately many of the answers are in the overview presented here on our FAQ page.

Regarding the spinner question, our fiberglass shop in Texas has been working on the spinners and back plates. Once they get the molding process figured out, we will be able to take the back plates and machine the matching holes in them to mate with the Hartzell prop. As some of you know, our glass shop took over Sam James operation and is making the James cowls also. So, as you can imagine that they are quite busy. Nonetheless I've been pestering Jimmy to get some spinners for us as soon as it's reasonably possible.

On other fronts, we finally moved into our new house last week and are working towards getting the shop up and running again. Finally! After only TWO years of construction.
 
On other fronts, we finally moved into our new house last week and are working towards getting the shop up and running again. Finally! After only TWO years of construction.

Very exciting! My detached 24x30 garage is coming up on a year of building. It was supposed to take 2-3 months.
 
Well it is time to move on in life and my F1 EVO has been sold to a gentleman in the USA.
I flew this plane for sixteen years and my many modifications added a lot of free speed to the aircraft. Absolutely my favourite aircraft, a blast to fly and a very versatile travelling machine. I flight planned 205 knots at 8000ft and 215 knots at 15,000. Fuel flows at altitude in the 10 to 12 gallon range. The tapered wing is marvellous and my thanks to Mark Fredrick for the design work.
Even with the larger engine I always used less fuel when travelling with RVs with four cylinder engines.
This aircraft won many of the cross country races that i participated in and I shall miss that kick in the butt acceleration on take off!
 
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